The present invention relates to a cover for packaging of cosmetic compositions and/or pharmaceutical compositions, to a packaging such as refillable packaging and sealed packaging for cosmetic and/or pharmaceutical compositions, and to cosmetic and/or pharmaceutical compositions packaged in the packaging.
Packagings for cosmetic compositions are typically provided with a rigid cover which prevents variation of the internal volume of the packaging. In the case of sealed packaging, a variation of the internal pressure, for example, an increase of the internal pressure induced by closing of the cover, or a variation of the external pressure, induces a difference of pressure between the interior and the exterior of the packaging.
This pressure variation has numerous disadvantages. On one hand, hermetic sealing of the packaging can be compromised leading to a risk of leakage of the cosmetic composition due to excessive internal pressure, or of contamination of the cosmetic composition due to internal low pressure. Furthermore, low pressure created by movement of the wall of the cover during opening of the packaging risks detaching the cosmetic composition and carrying it outside of its housing. Moreover, compression of the air tends to work against closing of the packaging, while external pressure not balanced by an equivalent internal pressure tends to work against opening of the packaging. This pressure variation occurs for containers with a sealed compartment.
Cosmetic compositions based on wax and emulsions of fatty material can advantageously be refilled within a container, particularly in the case of foundations, lipsticks, rouges or creams, by-products based on solvents, such as water, volatile silicones, alcohols or mixtures of them. These types of products require for their storage a packaging with a sealed compartment.
The sealed packagings for cosmetic compositions of known type have an elastomer seal with compression having an axial component. These packagings have numerous disadvantages. The sealed quality is only ensured if the elastomer seal is compressed with a relatively high force, making the closing of the packaging difficult or not very reliable. Furthermore, the packaging has a high price, due not only to the use of an expensive seal, but also due to difficulties of automation of the positioning of a non-rigid part, such as an elastomer seal.
One other problem with sealed cosmetic packaging concerns refills. Production of a packaging of a cosmetic composition by placing a refill inside a housing is known. The positioning and holding of the refill is not always easy. Moreover, the volume of the container receiving the refill increases the space requirement of the packaging. Furthermore, it is not always easy to ensure the temporary hermetic sealing of a sealed compartment of a refillable packaging for a cosmetic and/or pharmaceutical composition produced based on a volatile solvent.